This third-person action adventure game has crept into the shops with such a lack of fanfare that it comes a surprise to discover that it's good - even though it is produced by Toshihiro Nagoshi, of Super Monkey Ball fame. It casts you as Kiryu Kazuma, a former rising star of the Yakuza who emerges from a 10-year stretch for killing his boss to find that all the Yakuza families are after him, and the cop who locked him up is his only ally. A convoluted but enjoyable storyline, a beautifully realised Tokyo and an unpolished but thrillingly responsive street-fighting engine combine to create a most enjoyable game that blends the best aspects of the epic but sedate Shenmue and the superannuated arcade favourite Double Dragon. One for the connoisseurs.

Darkstar One PC, £29.99, Action line/Ascerony, 3 stars

Despite hushed reverence for the seminal Elite, freeform space operas have never sold particularly well. Darkstar One gives you control of a single spaceship that can be upgraded as you travel the cosmos, fighting or out-stealing pirates while unravelling the game's single-player campaign. You can either cruise around making your own fortune, or pick up missions at space stations that take the form of escorting, exploring or trading. The interface is easy and instinctive, allowing fluid combat almost from the off - although production niggles and occasional glitches will need some early patching. Darkstar's real problem is longevity, with the ease of piracy all but negating the need to buy any upgrades. Games like this need a major shot in the storyline to keep them from getting repetitive and Darkstar's thin, linear plot fails to deliver it. Still, it's an ambitious genre for a small publisher to try, and deserves the chance of a sequel.

Practical Intelligence Quotient Sony PSP, £19.99, D3, 3 stars

You can blame Nintendo for the current mental workout gaming craze. Their hugely successful Brain Training games have alerted other publishers to the profitable delights of intelligence based gaming. A host of titles are on the way, and one of the first is Practical Intelligence Quotient (PQ) for the PSP. While other brain games involve calculations or word association, PQ simply requires you to move your avatar to the exit of the room. Sounds easy? At first maybe, but it isn't long before the blocks, walls, escalators and other obstacles offer a severe reasoning test. Planning is essential and speed is of the essence. Unfortunately the camera is awkward, making things unnecessarily harder. And while Brain Training DS is simple enough to attract all, PQ's 3D manipulation will appeal more to gamers. Stark visuals complete what is a pleasingly different title for the PSP.

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